This invention is related to vapor receiving systems for use on gasoline dispensing nozzles and more particularly to a vapor receiving system which has a magnetic seal for contacting the fillpipe of the vehicle and a flexible bellows section.
Current environmental regulations will require in some areas that gasoline vapors displaced from a vehicle fuel tank being filled are to be recovered in order to prevent their escape into the atmosphere. One method of complying with this requirement is to have a closed filling system where the vapors displaced from the fuel tank are forced back into the underground hydrocarbon storage tanks. One problem encountered with this direct displacement system is obtaining a tight seal on the fillpipe of the vehicle so that the vapors are displaced into the vapor receiving system and back into the underground tanks rather than out into the atmosphere.
Another problem is obtaining a sealing surface for the vapor receiving system which is durable enough to withstand continuous use for several months without repair, and still maintain its sealing ability. Remedying this problem is complicated further when a magnetic device is used to hold the sealing surface of the vapor receiving system against the fillpipe, since the thicker the sealer surface becomes, the more the magnetic force is reduced.
To further aid in permitting the sealing surface of the vapor receiving system to contact the fillpipe, it is desirable to have the bellows portion of the vapor receiving system as flexible as possible, but yet durable enough to withstand continuous compression from use for several months without developing leaks.